The conventional treatment of skin disorders such as ichthyotic dermatoses, hyperkeratosis and related conditions has included topical application to the affected area of skin of ointments, creams, lotions or powders containing one or more of a wide variety of active ingredients such as organic and inorganic acids, steroids, fungicides, antibiotics and anti-inflammatory substances.
Usually, remission of the disorder is slow and frequently incomplete. Complete remission and cure of some skin conditions can usually only be obtained by the use of potent drugs, such as steroids, having often severe contra indications which limit their widespread use without medical supervision. Also, the topical application of caustic chemicals in the treatment of localised conditions, such as warts, is often accompanied by pain or discomfort which also limits their use.
It has been suggested in the clinical literature that certain skin disorders are due to insufficient acidity in the epidermal acid layer or coat of the skin. Accordingly, certain skin conditions including one reported case of ichthyosis were apparently successfully treated by lowering the pH of the patient's acid coat. The treatment included topical application of a 3% buffered lactic acid-containing cream.
The use of certain esters of pyroglutamic acid as auxiliary agents for accelerating absorption of drugs through the skin is described in JA 60-214 744 (Nitto Denki Kogyo KK). No curative benefit for the esters per se is mentioned.
Cosmetics containing one or more compositions obtained by the esterification of 2-pyrrolidone-5-carboxylic acid (PCA) and a fatty acid chosen from straight chain higher fatty acid are described in JA 57-185209 (Nisshin Seiyu KK). These are described as novel oily materials for cosmetic use. There is no suggestion that these materials could have any curative benefit in the treatment of skin disorders.
It has now been discovered that certain skin disorders may be treated successfully to at least reduce their symptoms, by topical application of a safe, effective curative agent chosen from certain esters of pyroglutamic acid. These esters are free from the contra indications associated with the topical applications of certain drugs.